The North Atlantic Oscillation (NAO) obtained using instrumental and documentary proxy predictors from Eurasia is found to be characterized by a ~60-year dominant oscillation since 1650. This pattern emerges clearly once the NAO record is time integrated to stress its comparison with the temperature record. The integrated NAO (INAO) is found to well correlate with the Length of the Day (LOD) (since 1650) and the global surface sea temperature (SST) record (since 1850). These findings suggest that INAO is an excellent proxy for global climate change, and that a ~60-year cycle exists in the global climate since at least 1700. Finally, the INAO ~60-year oscillation well correlates with the ~60-year oscillations found in the historical European aurora record since 1700, which suggests that this ~60-year dominant climatic cycle has a solar-astronomical origin.

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The El Niño Southern Oscillation (ENSO) is the Earth's strongest climate fluctuation on inter-annual time-scales and has global impacts although originating in the tropical Pacific. Many point indices have been developed to describe ENSO but the Multivariate ENSO Index (MEI) is considered the most representative since it links six different meteorological parameters measured over the tropical Pacific. Extreme values of MEI are correlated to the extreme values of atmospheric CO 2 concentration rate variations and negatively correlated to equivalent scale extreme values of the length of day (LOD) rate variation. We evaluate a first order conversion function between MEI and the other two indexes using their annual rate of variation. The quantification of the strength of the coupling herein evaluated provides a quantitative measure to test the accuracy of theoretical model predictions. Our results further confirm the idea that the major local and global Earth-atmosphere system mechanisms are significantly coupled and synchronized to each other at multiple scales.

We investigate the relationship between synoptic/local meteorological patterns and PM10 air pollution\ud levels in the metropolitan area of Naples, Italy. We found that severe air pollution crises occurred when\ud the 850 and 500 hpa geopotential heights and their relative temperatures present maximum values\ud above the city. The most relevant synoptic parameter was the 850 hPa geopotential height, which is\ud located about 1500 m of altitude. We compared local meteorological conditions (specifically wind stress,\ud rain amount and thermal inversion) against the urban air pollution levels from 2009 to 2013. We found\ud several empirical criteria for forecasting high daily PM10 air pollution levels in Naples. Pollution crises\ud occurred when (a) the wind stress was between 1 and 2 m/s, (b) the thermal inversion between two\ud strategic locations was at least 3C/200 m and (c) it did not significantly rain for at least 7 days. Beside\ud these meteorological conditions, severe pollution crises occurred also during festivals when fireworks\ud and bonfires are lighted, and during anomalous breeze conditions and severe fire accidents. Finally, we\ud propose a basic model to predict PM10 concentration levels from local meteorological conditions that\ud can be easily forecast a few days in advance. The synthetic PM10 record predicted by the model was\ud found to correlate with the PM10 observations with a correlation coefficient close to 0.80 with a con-\ud fidence level greater than 99%. The proposed model is expected to provide reliable information to city\ud officials to carry out practical strategies to mitigate air pollution effects. Although the proposed model\ud equation is calibrated on the topographical and meteorological conditions of Naples, it should be easily\ud adaptable to alternative locations